Device for spirally twisting blades for cutter-heads.



0. 1). MARSH, DEGD. I. I. STRYKER, ADMINISTRATOR. DEVICE FOR SPIRALLYTWISTING BLADES FOR CUTTER HEADS.

APPLIQATION FILED MAR. 31 1910.

Patented Oct. 3; 1911.

l SATE PAT nib.

CALVIN D. MARSH, 0F WILLIAMSPORT, PENNSYLVANIA; FRANK F. STRYKER, OFWILLIAMSPORT, PENNSYLVANIA, ADMINISTRATOR 0F SAID CALVIN D. MARSH,DECEASED, ASSIGNOR TO HERMANCE MACHINE (30., 0F WILLIAMSPORT, PENNSYL-VANIA, A CORPORATION OF PENNSYLVANIA.

DEVICE FOR SPIRALLY TWISTING BLADES FOR CUTTERHEADS.

Specification of Letters Patent.

Patented Oct. 3, 1911.

Application filed March 31, 1910. Serial No. 552,719.

To all whom it may concern:

Be it known that I, CALVIN D. MARSH, a citizen of the United States,residing at lVilliamsport, in the county of Lycoming and State ofPennsylvania, have invented a new and useful Device for SpirallyTwisting Blades for Cutter-Heads, of which the following is aspecification.

The invention relates to a device for spirally twisting blades forcutter heads.

The object of the present invention is to provide a simple, inexpensiveand eflicient device, designed to give a twist and imparta spiral formto thin blades of high speed steel, and capable of enabling pressure tobe rapidly applied to the blades at one or more points, whereby heavyjaws containing a relatively large amount of metal may be employed andpressure applied to the thin blades before the latter are cooled by thejaws.

WVith these and other objects in view, the invention consists in theconstruction and novel combination of parts hereinafter fully described,illustrated in the accompanying drawing, and pointed out in the claimshereto appended; it being understood that various changes in the form,proportion, size and minor details of construction, within the scope ofthe claims, may be re sorted to without departing from the spirit orsacrificing any of the advantages of the invention.

In the drawing :Figure 1 is a plan view of a blade twisting device,constructed in accordance with this invention. Fig. 2 is a transversesectional view of the same. Fig. 3 is a detail perspective view of thehead of the cam lever. Fig. 4 is an edge view of a blade, showing thesame before it is operated on by the device. Fig. 5 is a similar View,showing a spirally twisted blade after the same has been operated on bythe device.

Like numerals of reference designate corresponding parts in all thefigures of the drawing.

In the embodiment of the invention illustrated in the accompanyingdrawing, 1 designates a horizontal base carrying a stationary jaw 2 andsupporting a movable jaw 3. The stationary jaw 2, which may be formedintegral with the base or fixed to the same by any suitable means, isarranged longitudinally of the device at the back of the base, whichextends in advance of the stationary jaw to receive the movable jaw 3.The front engaging face 4 of the stationary aw is spirally arranged andthe inner or rear face 5 of the movable jaw is spirally disposed andconforms to the configuration of the engaging face 4 of the rear jaw.

The movable jaw is slidable on the upper face of base, being movedforwardly and rearwardly by the means hereinafter described, and it isprovided at the bottom with a transversely disposed slide ,6, arrangedin a transverse guide-way of the base. The guide-way, which is formed inthe base, consists of a rear opening 7 and a front groove 8. The rearopening 7 extends beneath the rear jaw, and the front groove 8, forms acontinuation of the rear opening and extends in advance of thestationary jaw, but preferably terminating short of the front edge ofthe base to form a front wall '9. The transverse slide 6, which islocated below the planes of the jaws, is preferably formed integral withthe movable jaw, but it may be rigidly connected therewith by anysuitable means. A straight fiat blade 10 of thin high speed steel, orother suitable material, is introduced between the jaws in a heatedcondition, and owing to the relatively large amount of metal containedin the jaws, it is necessary that pressure be rapidly applied to theblade before the same is cooled through contact with the shaping jaws.This is effected by means of a cam lever 11, provided at one end with ahead 12, eccentrioally pivoted to the upper face of the base by avertical bolt 13, and adapted to swing horizontally to actuate themovable jaw and to force the same into engagement with the blade. Theouter end of the lever is shaped into a handle or grip, and the head,which is provided with an upwardly extended eccentrically curved flange14 for applying pressure to the blade, has an eccentrically arrangedslot 15, receiving a pin or projection 16 of the slide, and adapted topermit the lever to actuate the sliding jaw in the outward movementthereof. The slot 15 is of a width greater than the projection 16, sothat the latter is not subjected to the strain incident to applyingpressure to the movable jaw. As soon as the movable jaw engages theblade, the eccentrically arranged face formed by the curved flange 14,engages the outer or front side face of the movable jaw, which is forcedinwardly or rearwardly until the blade is tightly compressed between thetwo spiral engaging faces of the stationary and movable jaws. The camlever may be instantly operated to clamp the blade between the jaws, andafter this preliminary pressure is applied to the blade through the camlever, increased pressure is exerted by means of a horizontal screw 17arranged approximately at right angles to the lever and having athreaded portion 18, operating through a threaded opening 19 in thecurved flange 14E of the head of the cam lever. The curved flange ispreferably enlarged at the opening 19, and the screw, which is providedat its outer end with an operating handle 20, is located at a point nearthe center'of the curved flange and in advance of the inner or rearportion, which in practice engages the movable jaw when the lever is atthe limit of its inward or clamping movement, as illustrated in Fig. 1of the drawings. The screw may then be operated to apply increasedpressure to the jaws at a different point from that engaged by the headof the cam lever. By this construction pressure may be applied to theblade with sufficient rapidity to insure a proper shaping of the bladebefore the same is cooled through contact with the clamping jaws. henthe blade 10, which is twisted by the jaws, is removed from the device,it retains the twisted or spiral form, as shown at 11 in Fig. 5 of thedrawing. The fric' tional engagement of the screw 17 with the movablejaw will prevent movement of the lever during the operation of thescrew.

The pivot of the cam lever may be mounted in various ways. In theaccompanying drawing the pivot bolt 13 is provided at the lower end witha nut 21, which may be locked against rotation by one or more fasteningdevices 22. The nut is located at the lower face of the base, which isprovided with integral supporting portions or feet 23, adapted toelevate the base and support the bolt and its nut above the surface uponwhich the device is placed. \Vhile the device in the drawing is, forconvenience of illustration, constructed for operating on acomparatively short blade, it is designed to be made in various sizesfor shaping blades for the different cutter heads employed inwood-working machines.

Having thus fully described my invention, what I claim as new and desireto secure by Letters Patent, is

l. A device for imparting a spiral twist to straight blades includingstationary and movable jaws having opposite corresponding spirallydisposed blade-engaging faces, means located at the outer side of themovable jaw for applying a preliminary pressure to the jaws, andseparate means for applying increased pressure to the jaws at adifferent point along the exterior of the movable jaw.

2. A device for imparting a spiral twist to straight blades includingstationary and movable jaws having opposite corresponding spirallydisposed blade-engaging faces, means located at the outer side of themovable jaw for applying a preliminary pressure to the jaws, andseparate means carried by the said means for applying increased pressureto the jaws at a different point along the exterior of the movable jaw.

3. A device for imparting a spiral twist to straight blades includingtwo jaws or members having opposite spirally disposed blade-engagingfaces, a cam lever for applying preliminary pressure to the jaws ormembers, and a screw carried by the cam lever and arranged to applyincreased pres sure to the jaws at a different point from the cam lever.

4:. A device for imparting a spiral twist to straight blades includingtwo jaws or members having opposite spirally disposed blade-engagingfaces, a cam lever having a curved eccentrically arranged engagingflange and adapted to apply preliminary pressure to the jaws or members,and a screw mounted in a threaded opening of the flange and having aninner engaging end and provided at the outer end with operating means,said screw being arranged to apply pressure at a different point fromthe lever.

5. A device for imparting a spiral twist to straight blades including abase having a guide-way, a stationary jaw carried by the base, a movablejaw mounted on the base and having a slide operating in the guideway,said jaws having opposite spirally disposed blade-engaging faces, a camlever pivoted to the base and connected with the slide and having aneccentrically arranged flange for engaging the movable jaw, and a screwcarried by the cam lever and arranged to engage the movable jaw.

6. A device for imparting a spiral twist to stralght blades including abase having a transverse guide-way and provided with a stationary jawhaving a spirally disposed ing the said flange and arranged to engage 10blade engaging face, a movable jaw having the jaw at a different pointfrom the lever. a transversely disposed slide operating in In testimony,that I claim the foregoing the guide-Way and provided With a projecas myown, I have hereto affixed my signation, a cam lever eecentricallypivoted to the ture in the presence of tWo Witnesses.

base and having an eccentric slot receiving CALVIN D. MARSH. the slide,said cam lever being also provided l Vitnesses:

with an eccentrically arranged flange for J. H. ARNOLD,

engaging the movable jaw, and a screw pierc- P. E. STRYKER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

